Do Not Disturb on my Mac keeps enabling itself at midnight or after every reboot even though I do not have it scheduled. As you can see from the screenshot below, DND is not enabled at all. What could be causing DND to automatically enable? I am running El Capitan

I've seen this happen when you have DND on another i-device and both are signed-in with the same Apple ID. Is that the case here?
– fsbJul 3 '16 at 18:52

Sounds like a corrupted .plist file or cache to me. I'm too busy to hunt down the file where those would be stored right now, but maybe someone else can elaborate on this.
– RedEagle2000Jul 3 '16 at 19:17

1

I opened com.apple.notificationcenterui.<guid>.plist and set dndEnd and dndStart to zero. When I reboot, DND is no longer enabled
– RHPTJul 3 '16 at 19:42